Erythromelalgia.

Erythromelalgia, characterized by temperature-dependent redness, pain, and warmth in one or more extremities, may be a primary disease or occur secondarily to underlying illnesses. Myeloproliferative disorders (eg, essential thrombocythemia) and a number of other associations have been reported. Two cases are described: one associated with essential thrombocythemia and the other the first reported case associated with pernicious anemia.